Surface Finishing and Coating
Depending on our customers application requirement or wish, our fasteners can also be provided with various surface finishes or coatings. For this service we cooperate closely with our longterm partnerships that are invididually specialized on different surface finishes and coatings.
The classic electrogalvanizing process is still used as standard for most fasteners. For environmental reasons, however, chromates containing Cr(VI) are no longer used for post-treatment, but Cr(VI)-free passivations. Yellow and olive chromates which still contain Cr(VI) are currently excluded.
Thick-film passivation has proven and established itself as a substitute for Cr(VI)-containing yellow or olive chromates. Here a comparable corrosion resistance of the coating is achieved with the same layer thickness of the zinc coating.
The zinc flake coating has very good corrosion protection properties and is used in all industrial sectors (e.g. automotive industry, gas industry, wind power, etc.) The advantages here are that no hydrogen embrittlement occurs and the performance of the corrosion protection is maintained even at high temperatures (300°C). Additional lubricants (top coats) can be applied to optimize the friction coefficients for special applications. Well-known brand names such as Geomet or Delta Protekt coatings are requested here.
PTFE coatings offer excellent corrosion protection properties, which are used in the oil and energy producing industry, gas production and wind and coal power. This type of coating is known under the brand name Xylan© and can also be offered in various colours.